The "Fighting Machine" is really fighting! my country's first F-class 50MW heavy-duty gas turbine has made a new breakthrough

Produced by: Science Popularization China

Author: Yao Yu (University of Science and Technology of China)

Producer: China Science Expo

"When the rooster crows, the world turns white." On March 8, 2023, accompanied by a loud mechanical roar, a "pride machine" from China was officially put into commercial operation after 72+24 hours of trial operation in Qingyuan, Guangdong. This is my country's first independently developed F-class 50MW heavy-duty gas turbine generator set G50. Its birth completed the technological breakthrough from "0" to "1", making China have 100% purely domestically produced heavy-duty gas turbines.

my country's first independently developed F-class 50MW heavy-duty gas turbine is commercially available

(Photo source: CCTV13 Morning News)

This "competitive machine" is not ordinary. Its operating temperature exceeds 1300℃, close to the high temperature of volcanic magma, and its working pressure reaches 18 atmospheres, which is equivalent to the water pressure at a depth of 180 meters under the sea. In such a harsh high temperature and high pressure environment, the gas turbine has to rotate at a high speed of 6000 revolutions per minute, and the linear speed is more than twice the flight speed of a large passenger aircraft. When it is in combined cycle, the power generation in one hour exceeds 70,000 kilowatt-hours, which can meet the electricity demand of 7,000 households for one day. Compared with the thermal power generating units of the same power, the G50 heavy-duty gas turbine can reduce carbon emissions by more than 500,000 tons a year.

Why are heavy-load gas turbines called "pride machines"?

Just as the steam engine set off the craze of the First Industrial Revolution, gas turbines are strategic equipment for national energy security and defense security in the new era. They are widely used in various fields such as national defense, transportation, energy, and environmental protection. Heavy-duty gas turbines are the "heart" of advanced power generation equipment, aviation equipment, military ships (aircraft carriers and submarines), and other major national weapons.

F-class 50MW heavy-duty gas turbine

(Photo source: China News Service)

The energy conversion method of gas turbine is the same as that of steam engine, that is, both convert the chemical energy of fuel into power (or electricity). The difference is that steam engine boils water, and when water is turned into steam, its volume expands, thereby driving the piston (or other power machinery such as steam turbine) to do work.

Schematic diagram of the working principle of a steam engine. Fire heats water in a boiler (blue), which turns into steam (pink). The steam expands and pushes the piston to reciprocate.

Image source: Wikipedia

Gas turbines do not require heated steam as an intermediate medium, but instead pass the gas directly into the turbine to expand and do work. This requires that the components of the gas turbine be able to withstand extreme high temperatures, high pressures, and high speeds for a long time and ensure the safe and stable operation of the entire machine. Higher operating parameters also significantly improve the work capacity of the equipment, enabling the gas turbine to have the characteristics of high unit power, fast starting speed, strong maneuverability, and high energy conversion rate.

When a gas turbine is working, it continuously draws in air from the atmosphere and compresses it. The compressed air is sent into the combustion chamber, fully mixed with the injected fuel and then burned to become high-temperature, high-pressure combustion gas, which is then passed into the gas turbine to drive the turbine impeller to rotate and expand to do work. The output power can be used as power or converted into electricity.

Gas turbine structure diagram

(Image source: http://www.timetoast.com/timelines/abel-project-tl)

Gas turbines are known as the "crown jewel" of the equipment manufacturing industry, especially heavy-duty gas turbines, which are known as one of the "most difficult mechanical equipment to manufacture in the world". They are composed of tens of thousands of parts and involve many fields such as machinery, metallurgy, materials, chemical industry, energy, electronics, information, etc., covering the cross-integration of basic disciplines and engineering technologies such as aerodynamics, engineering thermodynamics, combustion, structural mechanics, control theory, materials science, and manufacturing processes. Its research and development reflects a country's scientific and technological level and comprehensive national strength.

The production line robot places the finished blades

(Photo source: China News Service)

The development of heavy-duty gas turbines is a complex system engineering project with high technical difficulty, large R&D investment and long implementation cycle. Since the birth of the world's first heavy-duty gas turbine for power generation in 1939, heavy-duty gas turbines have undergone several technological innovations and industrial restructuring. Only a few countries such as the United States, Japan and Germany have the ability to independently develop heavy-duty gas turbines.

Heavy-duty gas turbine G50 complete machine test bench

(Photo source: Dongfang Steam Turbine Co., Ltd.)

In order to serve the country's major strategies, my country has established the "Aero Engine and Gas Turbine" National Science and Technology Major Project ("Two Engine Project"), and the National Energy Administration has listed the F-class 50MW heavy-duty gas turbine as the first major technical equipment demonstration project in the energy field. With the strong support of the country, central enterprises such as Dongfang Electric have formed a scientific research team in conjunction with universities and research institutes, coordinated the upstream, midstream and downstream enterprises in the industrial chain to gather advantageous resources, and launched a hard-working independent research and development journey. Since the research and development began in 2009, good news has been reported frequently. In 2016, the first batch of compressor, burner, and turbine component-level test benches in China were built. In 2018, the compressor and burner were successfully developed. In 2019, 100% independent manufacturing of all high-temperature components was achieved. The whole machine ignition test was successful once, and it was operated to 100% load for the first time in 2020. At the end of 2022, a successful ignition was achieved in Qingyuan, Huadian, and it will officially enter commercial operation in 2023.

Production and assembly process of heavy-duty gas turbines

(Photo source: CCTV13 Morning News)

In just 13 years, my country's heavy-duty gas turbines have gone through the entire process from basic theory, unit technology, component experiments, system integration, comprehensive verification, and product application, leapfrogging the path of development that took Western countries decades to complete. my country has truly mastered the 100% localization capabilities of independent design, manufacturing, testing, and commercial operation of heavy-duty gas turbines, creating a safe, controllable, independent and reliable gas turbine industry chain, filling the gap in my country's independent gas turbine application field.

Although the current commercial F-class 50MW heavy-duty gas turbine generator set G50 is still a certain distance away from the world's most advanced level, the independent design system built, the core methods mastered, the independent intellectual property rights established, and the high-quality talent team cultivated will all drive the coordinated development of the gas turbine discipline and industry.

The first domestically produced high-efficiency heavy-duty gas turbine rolled off the production line

(Photo source: CCTV13 Morning News)

What is more gratifying is that the first domestically produced air-cooled heavy-duty gas turbine with the highest energy efficiency level has been successfully rolled off the production line in Qinhuangdao, Hebei Province, with a power generation efficiency of over 64%, representing the most advanced technology in the current gas turbine power generation industry and becoming the most efficient heat-to-work conversion equipment in the world today. The new generation of gas turbines will become a powerful weapon for my country to achieve "carbon peak and carbon neutrality", and will also give the national heavy equipment that safeguards national security a stronger heart. The story of the domestically produced "self-respecting machine" continues, so let's wait and see!